Noncorrosive liquid for fluid systems



' MORTON ROLAND 'SHERBINO, OF DETROIT, MICHIGAN, ASSIGNOR TO HYI DBAULIC BRAKE COMPANY, OF DETROIT, MICHIGAN, A CORPORATION OF CALIFORNIA.

NONGORROSTVE LIQUID FOR, FLUID SYSTEMS.

No Drawing.

This invention concerns rendering the corrosive fatty acids present in castor oil harmless to copper by saponifying the fatty acids, leaving the resulting soap in solution.

Heretofore, it has been common practice to use a solution of alcohol and castor oil in substantially equal propbrtions as the actuating fluid medium of so-called hydraulic braking systems. This solution has been used because of the fact that Castor oil thus dissolved in alcohol has no detrimental effect upon the rubber used for cup Washers and for piping, and that at the temperatures encountered in practice, has a sufliciently constant viscosity for practical purposes.

It has been found in practice that even chemically pure castor oil, when mixed with any corrosion of copper, causing the copper to commerical alcohols, brings abouta gradual eventually dissolve in the castor oil.

I have found that the corrosion of the copper is greatly decreased by the saponification of the fatty acid present in the castor oil. By employing an alkali soluble in alcohol, such as sodium .or potassium hydroxide, and adding the required amount (determined by the-quantity of fatty acid prescut) to such an alcohol and castor oil solution as above described, there results an alposed to copper which comprises a solution cohol and castor oil solution of substantially equal proportions which is sufiiciently free from fatty acids as to preclude any'attack on coppermetal used in the braking systems.

The amount of alkali necessary to bring about the saponification of the fatty acid can be roughly calculated by multiplying the percentage of fatty acid by eight, which gives the grams of alkali necessary per gallonI of castor oil.

(KOH), as the resulting soap, being a liquid, is much less afiected by cold temperaprefer to use potassium hydroxide Application filed March 19, 1926; Serial No. 96,085.

ponification of the fatty acid with the re-.

sulting soap left in solution as an inert substance. v

3. The method of rendering a solution of ca'stor oil and alcohol non-corrosive to copperdwhich consists in saponifying the fatty ac1 4. The method of minimizing the corrosive effect of a castor oil and alcohol solution upon copper which'consists in saponifying the fatty acidof the oil and leaving the ,saponification products thereof in the solution. 7

5. A liquid medium of a fluid system exposed to copper, which comprises a solution of alcohol and an oil soluble therein and a product held in the solution and formed by the' saponification of the fatty acid of the castor oil. 7

6. A liquid medium for a fluid system exof alcohol and castor oil containing a small quanity of potassium hydroxide for the pur pose specified.

7. In a fluid brake system, the combination with a liquid medium, comprising castor oil,

in contact with metallic copper of means carried in the medium for minimizlng the destructive action of the fatty acid of the oil upon the copper, said means compr1s-' ing an alkali for saponifyino' the fatty acid.

In witness wheredf, I hereunto subscribe:

name this 2nd da 'of March, 1926.

MORTON no NnsHE BnIo. 

